I wouldn't trust that lock to keep a 16 ton weight from "walking away by itself," even if I WERE watching it out of a window (be honest with yourself, as much as you love it, you look away from the bike for a minute or two now and again, otherwise you wouldn't be on the other side of a window from it in the first place).

It is, admittedly, more secure than the old trick of weaving a bungee through the spokes, but only just.

A cable of the modern braided and shielded variety is perfectly suitable for preventing the old grab and run, but ONLY if the lock itself (as we see) isn't something you can just break with your bare hands (and the non casual thieves know exactly which models these are).

And of course you should always strive to park next to a nicer bike with a worse lock than yours.